Gadgil Priyadarshini, Hachmeister Kathleen A, Smith J Scott, Kropf Donald H
The Food Science Institute, Kansas State University, Manhattan 66506, USA.
J Agric Food Chem. 2002 Sep 25;50(20):5746-50. doi: 10.1021/jf020323+.
Alkylcyclobutanones have been recognized as chemical markers of irradiated lipid-containing foods since 1970. They are important because they are produced solely as a result of irradiation and not any other processing method. This study investigated the formation of 2-dodecylcyclobutanone (2-DCB) and 2-tetradec-5'-enylcyclobutanone (2-TDCB) in irradiated ground beef patties from commercial and noncommercial sources. Patties were irradiated using a (60)C source (gamma-irradiation) and electron beam irradiation, at five targeted absorbed doses of 0.5, 1.0, 2.5, 5.0, and 7.0 kGy. Commercially available irradiated patties were also studied. A supercritical fluid extraction (SFE) procedure was optimized and used for the extraction and isolation of the alkylcyclobutanones. Samples can be used for extraction without a prior cleanup step, which makes this procedure rapid and convenient to use. Identification and quantitation of the cyclobutanones were done by gas chromatography-mass spectroscopy. 2-DCB was detected in all of the irradiated samples (including commercial patties), and its concentration increased linearly with the irradiation dose. Electron beam irradiation produced a greater amount of 2-DCB compared to gamma-irradiation at dose levels >2.5 kGy. 2-TDCB was detected only at the two higher irradiation doses, whereas both marker compounds were not detected in the non-irradiated samples.
自1970年以来，烷基环丁酮一直被认为是辐照含脂食品的化学标志物。它们很重要，因为它们是仅由辐照产生的，而非任何其他加工方法。本研究调查了来自商业和非商业来源的辐照牛肉饼中2-十二烷基环丁酮（2-DCB）和2-十四碳-5'-烯基环丁酮（2-TDCB）的形成情况。使用（60）C源（γ辐照）和电子束辐照对肉饼进行辐照，目标吸收剂量为0.5、1.0、2.5、5.0和7.0千戈瑞。还研究了市售的辐照肉饼。优化了超临界流体萃取（SFE）程序，并用于烷基环丁酮的萃取和分离。样品无需预先净化步骤即可用于萃取，这使得该程序快速且易于使用。通过气相色谱-质谱法对环丁酮进行鉴定和定量。在所有辐照样品（包括市售肉饼）中均检测到2-DCB，其浓度随辐照剂量呈线性增加。在剂量水平>2.5千戈瑞时，与γ辐照相比，电子束辐照产生的2-DCB量更多。仅在两个较高辐照剂量下检测到2-TDCB，而在未辐照样品中未检测到这两种标志物化合物。
